Certain clinical and necropsy cardiac findings are described in 3 men who had percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending (LAD) coronary artery 80, 90 and 150 days, respectively, before sudden death. Each patient had a decrease in the mean transstenotic coronary gradient of 17, 38 and 43 mm Hg, respectively, and an angiographic increase in the LAD luminal diameter of 55, 60 and 65%, respectively. At necropsy, the LAD coronary artery in the area of the PTCA in each patient was narrowed 76 to 95% in cross-sectional area by therosclerotic plaques. No cracks in plaques or other lesions which may have resulted from the PTCA procedure were identified histologically in the LAD coronary artery of any patient.